1. Field of the Invention
The present invention relates generally to the fabrication of magnetic heads for hard disk drives, and particularly to the fabrication of insulation layers within the read head portions of such magnetic heads.
2. Description of the Prior Art
To increase the areal data storage density of hard disks for hard disk drives, the data bits within the tracks upon such hard disks are written closer together, so that a greater number of bits per inch are recorded. To efficiently read data from a data track with such a greater number of bits, the read head portion of a magnetic head of a hard disk drive must be structured such that the resolution of the read heads is increased.
The read heads of the prior art magnetic heads are fabricated utilizing thin film deposition techniques on an upper surface of a wafer substrate. In fabricating the read head portion, a first electrical insulation layer is deposited upon the surface of the substrate, followed by the deposition of a magnetic shield, followed by a first gap insulation layer, followed by the fabrication of a plurality of layers and structures that generally include a plurality of active read head magnetic layers, magnetic hard bias elements and electrical lead traces. Thereafter, a second gap insulation layer is deposited, followed by a second magnetic shield, another insulation layer, and further magnetic head components such as write head structures, that complete the magnetic head.
One of the problems associated with prior art read heads so designed is that they have thick gap insulation layers. Consequently, the prior art read heads display low resolution because resolution is adversely affected by the spacing between the two magnetic shields i.e. thicker the gap insulation layers, greater the spacing between the two magnetic shields and lower the resolution. Even read heads designed with thinner gap insulation layers are not free of problems. One of the problems associated with prior art read heads with thinner gap insulation layers is the increased potential for electrical shorts between the electrical leads (and the sensor) and the magnetic shields due to the thinness of the gap insulation layers. Another problem associated with prior art read heads with thinner gap insulation layers is the lack of efficient electrical insulation. In these read heads, the gap insulation layers are so thin that they are unable to perform the function of electrical insulation effectively.
The present invention seeks to solve these problems associated with prior art read heads by providing new gap materials and deposition methods to produce thinner gap insulation layers that ensure high resolution of the read heads and that also provide robust electrical insulation.